In recent decades, electric pumps have gradually replaced the conventional mechanical pumps and are widely used in heat circulation systems. The electric pumps have advantages of little electromagnetic interference, being efficient and environmental friendly, and stepless speed regulation etc., thus can meet the requirements of market well.
The electric pump includes an impeller and a rotor, and the impeller and the rotor rotate around a shaft. The position of the impeller is limited by a position-limiting device in an axial direction of the shaft. However, when the electric pump operates, the position-limiting device may rotate relative to the shaft, which may cause abrasion of the position-limiting device, and even a function failure of the position-limiting device.
Therefore, it is necessary to improve the conventional technology, to address the above technical issues.